Here is the full list of all 35 Postal III achievements.
50 kills using boomerang machete.
Kill/incapacitate 235 terrorists.
Finish your business with Krotchy.
Smash 50 windows.
Escape from prison.
200 kills using M-60.
50 kills using bees.
Taze 200 victims.
100 kills using machete in melee.
50 kills using cat.
150 kills using fire.
Destroy 50 cars.
300 headshot/decap kills.
Return Thegways to the owner
Choose path for the first time.
Make Venezuela peacemakers go home.
Beat the game once. No restrictions apply. Everyone's a winner.
Take out all the criminal scum infesting Catharsis!
Arrest eco zealots leader.
Disobey orders, given to you, and see what happens.
Injure yourself.
Piss 100 gallons of urine.
Beat game with zero kills.n(zombies and bosses don't count)
Suck up 500 items with the shop vac.
Arrest 200 perps.
Kill no animals in one playthrough.
Complete game using only melee.
Complete game using only the pistol.
Complete Good path without falling off.
Euthanise 30 elderly folks.
Kill 1000 unarmed bystanders.
Complete game killing only males.
50 badgersaw kills.
Spend 900 seconds or more in catnip bullet time.
Respawn 20 times.